JP2007084014A - Side airbag device for rear seat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a side airbag device for a rear seat capable of performing adequate impact suppression to an occupant seated in the rear seat having a reclining mechanism in side collision. <P>SOLUTION: A backrest part 12a of a rear seat 12 is constituted in a tiltable arranging manner to the position where a part thereof overlaps a body side part other than a side door when viewed from the side of a vehicle and to the 100% overlapping position where the entire backrest overlaps the body side part other than the side door. An inflator 18 has two chambers. In a side impact, when the detection signal that the backrest part 12a is arranged at the 100% overlapping position is output from a detection means 27, the inflator 18 is operated by the command signal from a control unit 25 so that gas is generated only from one chamber, and the internal pressure in an airbag 17 in a deployed state is dropped. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rear seat side airbag device, and more particularly to a rear seat side airbag device with a reclining mechanism.

  A side airbag device is used to protect an occupant seated on a vehicle seat during a side collision (side collision) in the vehicle. The airbag of this type of airbag device is disposed inside the side portion of the backrest portion of the seat in a folded state. The airbag is deployed while inflating between the occupant seated on the seat and the body side portion when a predetermined impact or more is applied to the body side portion of the vehicle. As a result, the waist, abdomen, chest and shoulders of the occupant are separated from the body side of the vehicle by the deployed airbag, and the occupant does not directly collide with the body side, and the impact is caused by the airbag. It is weakened and acts on the passenger.

Conventionally, in the side airbag device, various improvements have been made mainly for the side airbag device for the front seat, and the side airbag device has been applied to the rear seat. As a side impact airbag device for automobiles suitable for rear seats, a side impact airbag device that can reduce the size of the entire seat back and shorten the reinforcing cloth has been proposed (Patent Document 1). reference). In this side airbag device, the airbag module is fixed to the front surface of the seat back frame, and the rear end of the reinforcing cloth whose front end is attached to the cleaving portion of the skin cover is fixed to the vehicle outer surface of the seat back frame. A bar is attached.
JP 11-91487 A

  In the side airbag device of Patent Document 1, the front and rear size of the entire seat bag can be reduced by the above configuration, and the reinforcing cloth is also shortened. However, this airbag device is not intended to solve the problems peculiar to the rear seat. The inventor of the present application indicates that the body side portion of the corresponding vehicle is different between the front seat and the rear seat of the vehicle, and the deformation state of the corresponding body side portion is different depending on the angle of the backrest portion in the rear seat provided with the reclining mechanism. This invention was completed paying attention to.

  The present invention has been made in view of the above-described conventional problems, and the purpose thereof is to perform more appropriate impact suppression for a passenger seated in a rear seat with a reclining mechanism at the time of a side collision. The object is to provide a side airbag device for a rear seat.

  In order to achieve the above object, the invention according to claim 1 is directed to air developed between a passenger seated in a rear seat with a reclining mechanism and a vehicle body side portion by gas generated from a gas generation source. A side airbag device for a rear seat provided with a bag, wherein a backrest portion of the rear seat is partially overlapped with a body side portion other than a side door when viewed from the side of the vehicle, Detection that detects the fact that the backrest portion is disposed at the 100% overlap position when viewed from the side of the vehicle, while being configured to be tiltable at a position that overlaps with the body side portion other than the door. Means, a side collision detecting means for detecting a side collision of the vehicle, an internal pressure reducing means for reducing the internal pressure in the deployed state of the airbag, and the backrest portion from the detecting means during the side collision If 0% overlap detection signal which is arranged at a position is outputted, and a control device for activating the pressure reducing means to reduce the internal pressure.

Here, the “vehicle body side portion” means a side door, a pillar, or the like disposed on the side portion of the vehicle.
The body side part of the vehicle corresponding to the front seat is a front door and a center pillar (B pillar), and when the vehicle collides, the front door and the center pillar are deformed into the vehicle compartment side of the beltline part (intrusion) Amount). On the other hand, the body side part of the vehicle corresponding to the rear seat is the rear part of the side door (rear door), the C pillar, the front part of the tire house, the rear quarter, and the like. Less than the amount of deformation.

  The airbag performs a more appropriate impact suppressing action in the case of an internal pressure corresponding to the amount of deformation of the body side portion at the time of a side collision. In the present invention, when the backrest portion of the rear seat is disposed at the 100% overlapping position as viewed from the side of the vehicle, it is detected by the detecting means. When a side collision occurs in a state where the backrest portion is disposed at the 100% overlap position, the internal pressure reducing means is operated by the control means so as to reduce the internal pressure of the airbag. As a result, when the airbag is deployed at a more appropriate internal pressure corresponding to a state where the deformation amount (intrusion amount) of the body side portion toward the occupant is small, an impact is transmitted to the occupant via the airbag. Impact is properly suppressed. In addition, when the backrest portion is disposed at a position other than the 100% overlapping position, an appropriate internal pressure is greater than when the backrest portion is disposed at the 100% overlapping position, and the impact is appropriately suppressed.

  According to a second aspect of the present invention, in the first aspect of the present invention, the airbag is installed in the rear seat. In this invention, even if the position of the backrest portion is changed by the action of the reclining mechanism, the positional relationship between the airbag storage position and the occupant does not change, so the position of the airbag in the deployed state is determined between the body side portion and the occupant. It is easier to dispose them at appropriate positions as compared with the case where the airbag is provided on the body side portion side.

  According to a third aspect of the present invention, in the invention of the first or second aspect, the airbag is provided with a vent hole, and the internal pressure reducing means increases the opening degree of the vent hole. Reduce internal pressure. As a method of increasing the opening degree of the vent hole, for example, there is a method of sewing a cloth or a film covering the vent hole with a seam and cutting the seam by moving the cloth by an operation of a micro gas generator.

  In this invention, when a side collision occurs in a state where the backrest portion is 100% overlapped, at least in a state where the deployment of the airbag is completed, the opening degree of the vent hole formed in the airbag becomes a large state, The internal pressure decreases as compared with the case where the opening degree of the vent hole does not increase.

  According to a fourth aspect of the present invention, in the first or second aspect of the present invention, the internal pressure reducing means reduces the internal pressure by suppressing the output of the gas generation source. In the present invention, when a side collision occurs with the backrest portion being 100% overlapped, the output of the gas generation source is suppressed, and therefore the output of the gas generation source is suppressed when the airbag has been deployed. The internal pressure of the airbag is reduced as compared with the case where it is not performed.

  According to a fifth aspect of the present invention, in the first or second aspect of the present invention, the gas generation source is an inflator having a plurality of chambers, and the internal pressure reducing means generates gas from the plurality of chambers. The internal pressure is reduced by selecting a chamber. According to the present invention, when a side collision occurs with the backrest portion 100% overlapped, an inflator having a plurality of chambers is operated, for example, in a state in which gas is generated from some selected chambers. The Accordingly, the amount of gas supplied to the airbag is reduced as compared with a state where all chambers are selected and gas is generated from all the chambers, and the internal pressure of the airbag is reduced. The selection of the chamber is not limited to a part or all of the chambers, and the chamber filled with the gas generating agent is selected corresponding to the state where the internal pressure should be reduced and the state where the internal pressure is not reduced. Also good.

  ADVANTAGE OF THE INVENTION According to this invention, the more suitable impact suppression can be performed with respect to the passenger | crew who seated on the backseat with a reclining mechanism in the case of a side collision.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a side airbag device embodying the present invention will be described with reference to FIGS. In the following description, when explaining the direction, the forward direction of the vehicle is described as the front, and the upper, lower, front, rear, left, and right are defined based on the forward direction. Suppose that the vehicle is along the above-mentioned directions with reference to the airbag at the time of deployment.

  As shown in FIG. 2, the vehicle 10 is provided with a front seat 11 and a rear seat 12. The back portion (seat back) 11 a of the front seat 11 is arranged so as to be located closer to the rear portion of the front door 13.

  The rear seat 12 has a reclining mechanism, and the backrest portion 12a of the rear seat 12 is rotatably supported at the rear end of the seat portion 12b via a hinge 12c constituting a part of the reclining mechanism. 12b can be reclined. The backrest portion 12a is disposed so as to straddle the rear portion of the rear door 14 and the rear quarter 15 constituting the body side portion in a state where the reclining mechanism is not operated. And the backrest part 12a is a part where it overlaps with the body side part other than the rear door 14 as a side door in the state seen from the side of the vehicle 10, and as shown by the chain line in FIG. It is configured to be able to be tilted and arranged at a 100% overlapping position that overlaps with the body side portion.

  FIG. 1A is a schematic side view of a state in which the side airbag device 16 of the left rear seat 12 is activated and the deployment of the airbag 17 is completed. The side airbag device 16 is provided on the body side portion side of the backrest portion 12a, and is embedded with an inflator 18 as a gas generation source and a folded airbag 17 accommodated in a case (not shown). ing. The side airbag device 16 is also installed in the right rear seat, and the front seat 11 is equipped with a known airbag device for the front seat. Hereinafter, the side airbag device 16 of the left rear seat 12 will be described.

  The inflator 18 is formed in a long shape extending substantially in the vertical direction along the backrest portion 12a. As shown in FIG. 3, the inflator 18 includes a cylindrical body 20 in which a plurality of gas discharge holes 19 are formed in the peripheral wall portion. The cylindrical body 20 has two chambers 21a and 21b partitioned by a partition wall 20a, and a gas generating agent (not shown) is filled in each chamber 21a and 21b. In each of the chambers 21a and 21b, an appropriate amount of a gas generating agent determined in advance through experiments or the like when gas is generated only from one chamber 21a and when gas is generated from both chambers 21a and 21b. Is filled.

  A filter 22 is disposed on the outer peripheral portion of the cylindrical body 20, and a casing 23 is attached to the outside of the filter 22. The filter 22 has a function of cooling the gas generated from the gas generating agent and a function of removing combustion residues contained in the gas. The casing 23 is formed with outlets 23a to 23d for blowing out gas generated from the gas generating agent from the inflator 18. In addition, initiators (igniters) 24 a and 24 b are provided at both ends of the inflator 18, and the initiators 24 a and 24 b are in a state where only one initiator 24 a is operated according to a command from the control unit 25. The state in which the initiators 24a and 24b are activated is selected. That is, either a state in which gas is generated from all the chambers 21 a and 21 b of the inflator 18 or a state in which gas is generated from some of the chambers 21 a is selected by a command signal from the control unit 25. The control unit 25 and the initiators 24a and 24b constitute an internal pressure reducing unit that reduces the internal pressure of the airbag 17 in the deployed state.

  The control unit 25 detects an impact on the body side portion of the vehicle 10 and detects an impact sensor 26 that detects a side impact based on the detection signal, and the backrest portion 12a is viewed from the side of the vehicle 10. In this state, it is electrically connected to the detecting means 27 for detecting that it is disposed at the 100% overlapping position. When the control unit 25 determines that a side collision has occurred based on the detection signal of the impact sensor 26, the detection unit 27 outputs a detection signal in which the backrest portion 12a is disposed at the 100% overlap position. An operation signal is output only to one initiator 24a, and in other cases, an operation signal is output to both initiators 24a and 24b. The control unit 25 causes the internal pressure reducing means to reduce the internal pressure in the deployed state of the airbag 17 when a detection signal in which the backrest 12a is 100% overlapped is output from the detection means 27 at the time of a side collision. The control means to be operated is configured.

  The impact sensor 26 is provided in a side door (for example, the front door 13) and is configured by a lateral acceleration sensor that detects lateral acceleration. The lateral acceleration sensor detects an impact applied to the side door from the side of the vehicle 10 as a lateral acceleration, and outputs a side collision signal when the magnitude is equal to or larger than a set value corresponding to the side collision.

  As the detection means 27, for example, a limit switch disposed at a position where the backrest portion 12a is turned on in a state where the backrest portion 12a is disposed at the 100% overlap position, an optical sensor, or an angle sensor for detecting the angle of the backrest portion 12a is used. .

  The airbag 17 is formed so as to form a bag shape as a whole by sewing a pair of base fabrics 30 made of a woven fabric or the like at their peripheral edges. The airbag 17 covers the inflator 18 in a state where the inflator 18 is located at the rear end portion of the airbag 17. As shown in FIG. 1B, the airbag 17 has portions K, M, H, respectively corresponding to the shoulder, chest, abdomen, and waist of the occupant P when viewed from the front side of the vehicle in the deployed state. The maximum values Kw, Mw, Hw, and Yw of the left and right width dimensions of Y are formed such that Kw> Mw> Hw> Yw. That is, the maximum value Kw of the portion K corresponding to the shoulder is larger than the maximum value Mw of the portion M corresponding to the chest, and the maximum value Mw of the portion M corresponding to the chest is larger than the maximum value Hw of the portion H corresponding to the abdomen. In addition, the maximum value Hw of the portion H corresponding to the abdomen is formed to be larger than the maximum value Yw of the portion Y corresponding to the waist.

  Three tethers 31a, 31b, and 31c are sewn between the left and right base fabrics 30 in order to regulate the left and right width dimensions of the portions K, M, H, and Y. Each tether 31a-31c is formed in a rectangular shape, and both side portions in the width direction (left-right direction in FIG. 1 (b)) of each tether 31a-31c extend over the entire length of both base fabrics 30 of the airbag 17. Each is joined to the inner surface. Each of the tethers 31a to 31c is formed so that the length in the width direction is tether 31a> tether 31b> tether 31c. More precisely, the tethers 31a to 31c extend in the front-rear direction in parallel with each other at positions corresponding to the boundaries of the portions K, M, H, and Y when the airbag 17 is deployed. The base fabric 30 is sewn so as to extend in a direction substantially perpendicular to the attachment line L to the portion 12a. In addition, illustration of the thread | yarn for sewing is abbreviate | omitted in the figure.

  In the airbag 17 in the deployed state, the outlet 23a of the inflator 18 is disposed at the rear end of the portion K, the outlet 23b of the inflator 18 is disposed at the rear end of the portion M, and the rear end of the portion H. The blowout port 23c of the inflator 18 is disposed in the portion, and the blowout port 23d of the inflator 18 is disposed in the rear end portion of the portion Y. The inflator 18 injects gas from the outlets 23a to 23d to the corresponding portions K, M, H, and Y. The air bag 17 is deployed from the folded state in the case toward the front of the vehicle by the gas generated from the inflator 18.

  Although the appropriate value varies depending on the vehicle type, in the evaluation using an AM50 dummy in a certain vehicle type (for example, a small passenger car), the maximum value Kw of the part K is preferably 150 to 250 mm, and the maximum value Yw of the part Y is preferably 30 to 100 mm. .

The portion Y is formed with a vent hole 28 for discharging the gas in the airbag 17 toward the vehicle body side.
Next, the operation of the side airbag device 16 configured as described above will be described.

  When the vehicle 10 receives an impact of a predetermined value or more, the impact sensor 26 outputs a detection signal (side collision signal). When the detection signal of the impact sensor 26 is input, the control unit 25 outputs an operation signal to one initiator 24a if a detection signal of a 100% overlap position is output from the detection means 27. Thereby, the inflator 18 generates gas only from one chamber 21a. The gas generated from the chamber 21a is sprayed from the outlets 23a to 23d to the portions K, M, H, and Y of the airbag 17 to deploy the airbag 17 (see FIG. 1A).

  Since gas is generated only from one chamber 21a, the internal pressure of the airbag 17 in the deployed state of 17 is lower than when gas is generated from both chambers 21a and 21b. However, since the backrest portion 12a is located at a 100% overlap position where the backrest portion 12a is viewed from the side of the vehicle 10 and overlaps with the body side portion other than the rear door 14, the backrest portion 12a is a portion corresponding to the rear seat 12. The deformation amount of the body side portion, that is, the intrusion amount into the vehicle interior is small. As a result, a state in which the internal pressure of the airbag 17 is low is an appropriate internal pressure, and appropriate impact suppression can be performed on the occupant P seated on the rear seat 12.

  On the other hand, if a part of the backrest 12a is in a state corresponding to the rear door 14 in the state where the side collision has occurred, the detection unit 27 does not output a detection signal of the 100% overlap position. An operation signal is output to the initiators 24a and 24b. As a result, the inflator 18 generates gas from both the chambers 21a and 21b, and the generated gas is jetted from the outlets 23a to 23d to the portions K, M, H, and Y of the airbag 17, and the airbag. 17 is developed. As a result, in the deployed state of the airbag 17, the internal pressure of the airbag 17 is higher than when the backrest portion 12a is disposed at the overlapping position. In the deformed state of the body side portion, the portion of the rear door 14 is larger than the other portions, so that the higher the internal pressure, the more appropriate impact suppression can be performed.

  Further, the door trim that is the body side portion corresponding to the rear seat 12 is deformed so that the deformation amount on the lower side, that is, the intrusion amount into the vehicle interior becomes large. When the maximum value of the left-right width dimension of the portion corresponding to the waist portion is equal to or greater than the maximum value of the left-right width dimension of the portion corresponding to the shoulder portion, as in the prior art airbag, it acts on the occupant P from the portion corresponding to the waist portion. The pressure becomes maximum, and the amount of movement between the chest and waist becomes relatively large, and an excessive force tends to act on the lower part of the spine.

  However, the airbag 17 according to this embodiment has the maximum values Kw, Mw, left and right width dimensions of the portions K, M, H, Y corresponding to the shoulder, chest, abdomen, and waist of the occupant P in the deployed state. The relationship between Hw and Yw is Kw> Mw> Hw> Yw. Therefore, when a side impact occurs, when the door trim of the rear door 14 and the occupant P that are deformed approach each other with the airbag 17 therebetween and an impact acts on the occupant P, the pressing force at the contact portion of the airbag 17 with the occupant P is applied. However, the portions K, M, H, and Y corresponding to the shoulder, chest, abdomen, and waist of the occupant P are substantially equal. As a result, the occupant P moves relative to the rear seat 12 in the vehicle width direction with the spine extending straight when viewed from the front, and an unreasonable force acts on the lower part of the spine. Is prevented.

This embodiment has the following effects.
(1) When viewed from the side of the vehicle 10, a side collision occurs in a state in which the backrest 12a of the rear seat 12 is disposed at a 100% overlapping position where it overlaps with the body side portion other than the side door (rear door 14). When this occurs, the internal pressure lowering means (initiators 24a and 24b) are actuated so as to reduce the internal pressure in the deployed state of the airbag 17. Specifically, only one initiator 24a is activated and gas is generated only from one chamber 21a. As a result, the airbag 17 is deployed with a more appropriate internal pressure corresponding to a state where the deformation amount (intrusion amount) of the body side portion toward the occupant P is small, and the impact is transmitted to the occupant P through the airbag 17. At that time, the impact on the occupant P is appropriately suppressed. Moreover, when the backrest part 12a is arrange | positioned in positions other than a 100% overlapping position, it becomes a suitable internal pressure larger than the case where it arrange | positions in a 100% overlapping position, and an impact is suppressed appropriately.

  (2) The airbag 17 is installed in the rear seat 12. Therefore, even if the position of the backrest portion 12a is changed by the action of the reclining mechanism, the positional relationship between the storage position of the airbag 17 and the occupant P does not change. Arranging at an appropriate position with respect to P is easier than when the airbag 17 is provided on the body side portion side.

  (3) The gas generation source is an inflator 18 having a plurality of chambers 21a and 21b, and the internal pressure lowering means generates gas from all the chambers 21a and 21b and gas from some chambers 21a. It is the structure which selects the state to perform. Therefore, by changing the inflator 18 without changing the configuration of the airbag 17 corresponding to the vehicle type, the side collision occurs in a state in which the internal pressure of the airbag 17 in the deployed state is 100% overlapped with the backrest portion 12a. When it occurs, the state can be reduced as compared with the case where a side collision occurs in other states.

  (4) When the airbag 17 is viewed from the front side of the vehicle in the deployed state, the left and right width dimensions of the portions K, M, H, and Y corresponding to the shoulder, chest, abdomen, and waist of the occupant P are maximum. The relationship between the values Kw, Mw, Hw, and Yw is formed such that Kw> Mw> Hw> Yw. Therefore, when an impact is transmitted to the occupant P through the airbag 17 at the time of a side collision of the vehicle 10, the impact force is applied from the airbag 17 to the side of the occupant P almost evenly. Therefore, compared with the case where an airbag having the same configuration as that of the airbag for the front seat, that is, an airbag in which the left and right width dimension of the part corresponding to the waist part is equal to or larger than the left and right width dimension of the other part is used. Impact is suppressed more appropriately.

  (5) Tethers 31a, 31b, and 31c are provided to restrict the left and right width dimensions of the portions K, M, H, and Y. Therefore, as compared with a method of forming a seam portion (stitched portion) by sewing a part of the airbag 17 with a thread as a method for regulating the lateral width dimension of the airbag 17, the necking of the airbag 17 is completed in the deployed state. It can be regulated to a desired dimension in a small state.

  (6) Since the airbag 17 is provided with the vent hole 28 in the portion Y corresponding to the waist portion, even if a large force is applied to the portion Y due to the deformation of the door trim at the time of a side collision, the gas in the portion Y As a result, a moderate cushioning action is exerted, and a large impact on the occupant P is suppressed.

  (7) At the rear end of the airbag 17 at a position corresponding to the portions K, M, H, and Y partitioned by the tethers 31a, 31b, and 31c, the outlets 23a, 23b, 23c, and 23d of the inflator 18 are provided. Is provided. Accordingly, the airbag 17 is rapidly deployed into a predetermined shape as compared with the case where the number of outlets is smaller than the number of portions K, M, H, and Y.

  (8) Since the portions K, M, H, and Y are not completely independent chambers and are configured to allow gas to flow between each other, when the airbag 17 acts on the occupant P, The pressure at the contact portion tends to be equal.

(Example of change)
The embodiment can also be embodied as follows.
As the internal pressure reduction means, the initiators 24a and 24b are configured to select a state in which only the other initiator 24b is activated and a state in which both initiators 24a and 24b are activated in accordance with a command from the control unit 25. Also good. In this case, one of a state in which gas is generated from all the chambers 21 a and 21 b of the inflator 18 and a state in which gas is generated from some of the chambers 21 b is selected by a command signal from the control unit 25.

  If the number of chambers constituting the inflator 18 is three or more and a side collision occurs with the backrest portion 12a of the rear seat 12 being 100% overlapped, gas is supplied from some chambers. In other cases, gas may be generated from all the chambers.

  The configuration for adjusting the internal pressure in the deployed state in accordance with the overlapping state of the backrest portion 12a is not limited to the configuration for selecting whether to generate gas from some chambers or to generate gas from all chambers. Different chambers each filled with a gas generating agent may be selected corresponding to a state where the pressure is to be reduced and a state where the internal pressure is not reduced.

  The internal pressure reducing means for reducing the internal pressure in the deployed state of the airbag 17 when the side impact occurs with the backrest portion 12a of the rear seat 12 being 100% overlapped is provided in the inflator 18 with the chambers 21a and 21b. It is not restricted to the structure which provides multiple and selects the chamber to operate. For example, a vent hole may be provided in the airbag 17 and a means for increasing the opening degree of the vent hole may be provided when it is necessary to reduce the internal pressure in the deployed state of the airbag 17. Specifically, as shown in FIGS. 4A and 4B, the retainer 41 constituting the side airbag device 16 has a pair of bolts 42 projecting rearward at two upper and lower portions. These bolts 42 are inserted into holes formed in the rear end edge of the airbag 17 and holes formed in the seat frame 43, and on the rear side of the seat frame 43 (on the right side in FIG. 4A). It is fastened and fixed by a nut 44 screwed into the protruding portion. A hole 45 is formed in the seat frame 43 near the fixing position of the retainer 41. A vent hole 46 having a smaller diameter than the hole 45 is formed in the base cloth 30 of the airbag 17 at a position corresponding to the hole 45 of the seat frame 43, and a cover cloth 47 or film covering the vent hole 46 is formed by the seam 48. The cloth 30 is sewn. The diameter of the contact cloth 47 is larger than the diameter of the vent hole 46 and smaller than the diameter of the hole 45. A plate 49 is fixed to the front side of the seat frame 43 at a position facing the hole 45 by a bolt 51 and a nut 52 with a predetermined distance from the front surface of the seat frame 43 via a spacer 50. The bolt 51 passes through the plate 49, the spacer 50, the base cloth 30, and the seat frame 43 in order, and a nut 52 is screwed into a portion protruding to the rear side (right side in FIG. 4A) of the seat frame 43 and tightened. It is fixed. An MGG (micro gas generator) 53 is fixed to the application cloth 47 side of the plate 49. The seam 48 can be cut by moving the application cloth 47 or the film by the operation of the MGG (micro gas generator) 53. In this case, the opening degree of the vent hole 46 is 0% when the MGG 53 is not operated, and the opening degree of the vent hole 46 is 100% after the MGG 53 is operated. In this configuration, when a side collision occurs in a state where the backrest 12a is 100% overlapped, the MGG 53 is actuated by a command signal from the control unit 25, and at least in a state where the airbag 17 has been deployed. The state of covering the vent hole 46 by the contact cloth 47 or the film is released, and the opening degree becomes large. Accordingly, the internal pressure is reduced as compared with the case where the opening degree of the vent hole 46 is not increased. The inflator of this embodiment has a retainer, and the inflator 18 is fixed inside the retainer 41.

-The vent hole 46 and MGG53 which comprise an internal pressure fall means may be provided not only in one place but in multiple places.
As a configuration for forming a vent hole using the operation of the MGG 53, a fragile portion is formed in the address cloth 47, and when the MGG 53 is operated, the seam 48 is broken instead of breaking the address cloth 47 so that the vent hole It is good also as a structure formed. Further, without forming a hole in the base fabric 30, a weak portion is provided in the portion of the base fabric 30 corresponding to the hole 45 of the seat frame 43, and when the MGG 53 is activated, the base fabric 30 is broken at the weak portion and vented. It is good also as a structure in which a hole is formed.

-An internal pressure reduction means is good also as a structure which reduces the said internal pressure by suppressing the output of a gas generation source. For example, the inflator 18 as a gas generation source is provided with a valve that discharges a part of the gas generated from the chamber to the outside without being supplied to the airbag 17, and the valve can be driven open by the MGG. In this configuration, when a side collision occurs in a state where the backrest is 100% overlapped, the MGG is actuated by a command signal from the control unit 25 to open the valve. Therefore, a part of the gas generated from the chamber of the inflator 18 is discharged to the outside without being supplied to the airbag 17, so that the internal pressure of the airbag 17 is lowered in the deployed state. If a side collision occurs in a state where the backrest is located at a position other than the 100% overlapping position, the MGG is not activated, and all the gas generated from the chamber of the inflator 18 is supplied to the airbag 17 and the internal pressure does not decrease.

  The airbag 17 is not limited to a configuration that is partitioned into four parts in the deployed state, and the airbag 17 corresponds to the shoulder portion by two tethers 31a and 31c as shown in FIG. 4C. It may be configured to be divided into a portion K to be performed, a portion MH corresponding to the chest and abdomen, and a portion Y corresponding to the waist. Here, the “part corresponding to the chest and abdomen” means a part obtained by combining a part corresponding to the chest and a part corresponding to the abdomen. Also in this case, in the case of a side collision, more appropriate impact suppression can be performed on the occupant P seated in the rear seat, as compared with a conventional airbag.

  -When the airbag 17 has been deployed, instead of using a tether as a method of regulating the left and right width dimensions of the portions K, M, H, MH, and Y, the seam between the opposing base fabrics 30 should be sewn with seams. It may be. Moreover, you may weld or adhere | attach between the right and left base fabrics 30 instead of a seam.

  The shape of the airbag 17 in the deployed state is not limited to a shape in which the length K in the front-rear direction corresponds to the shoulder portion is long and the portion Y corresponding to the waist portion is the shortest. For example, you may form so that the shape seen from the side of the vehicle 10 may become a substantially rectangular shape.

  The shape of the airbag 17 is not limited to the shape in which the maximum value of the left-right width dimension of each portion becomes larger as the upper portion of the airbag 17 in the deployed state. For example, as shown in FIG. The shape in which the maximum value of the left-right width dimension of the portion Y corresponding to the waist is equal to or greater than the maximum value of the left-right width dimension of the portion K corresponding to the shoulder portion may be used. In this case, as shown in FIG. 5 (a), the shape of the airbag 17 in the completed deployment state is formed with a notch 32 at a position corresponding to the upper arm so as not to restrain the upper arm of the occupant P more than necessary. The shape may be provided.

  -In the case of a side collision, as a configuration to give a moderate cushioning action to the portion corresponding to the portion Y of the airbag 17, instead of providing the vent hole 28 in the portion corresponding to the portion Y of the base fabric 30, a portion of the door trim An impact absorbing member may be provided at a location corresponding to Y. As the impact absorbing member, for example, a soft resin such as a thermoplastic elastomer or a foamed resin such as urethane foam is used.

  -The inflator 18 is not provided with the outlets 23a, 23b, 23c, 23d corresponding to the portions K, M, H, Y, etc. partitioned by the tethers 31a, 31b, 31c, etc. The number may be less than the number of each portion K, Y, etc. partitioned by the tethers 31a, 31b, 31c, etc. For example, one outlet may be used.

The side airbag device 16 is not limited to the configuration provided in the backrest portion 12a of the rear seat 12, and may be provided on the body side of the vehicle 10.
The technical idea that can be grasped from the embodiment will be described below.

  (1) In the side airbag device according to any one of claims 1 to 5, when the airbag is viewed from the front side of the vehicle in a deployed state, The relationship between the maximum value of the left and right width dimensions of the part corresponding to the waist is greater than the maximum value of the part corresponding to the shoulder and the part corresponding to the chest and abdomen, and the maximum value of the part corresponding to the chest and abdomen is It is formed to be larger than the maximum value of the portion corresponding to the waist.

  (2) In the side airbag device according to the technical idea (1), the airbag is provided with a tether to regulate the left-right width dimension of each portion, and gas is supplied to the airbag. The gas generation source to be provided has a blowout port for blowing out gas corresponding to each part defined by the tether.

  (3) In the invention described in claim 5, when the internal pressure is reduced, the internal pressure reducing means selects a part of the preset chambers as a chamber for generating gas, and when the internal pressure is not reduced, gas is supplied. All chambers are selected as chambers to be generated.

(A) is a side view schematically showing a state where the airbag is completely deployed when an occupant is seated on the seat, and (b) is an end view of the airbag taken along line 1b-1b in (a). The schematic side view which shows arrangement | positioning of the front seat and rear seat of a vehicle. The schematic diagram which shows the structure of an inflator. (A) is a schematic cross-sectional view showing the internal pressure lowering means of the modified example, (b) is a schematic view of the portion corresponding to the vent hole of (a) as seen from the rear side of the seat frame, and (c) is the airbag of the modified example FIG. 2 is an end view corresponding to FIG. (A) is a side view schematically showing a deployment state of an airbag according to a modified example, and (b) is an end view taken along line 5b-5b of (a).

Explanation of symbols

  P ... occupant, 10 ... vehicle, 12 ... rear seat, 12a ... backrest, 12c ... hinge constituting reclining mechanism, 17 ... air bag, 18 ... inflator, 21a, 21b ... chamber, 24a, 24b ... internal pressure reducing means. Constructing initiator, 25... Control section as control means, 26. Shock sensor as side collision detection means, 27... Detecting means, 46... Vent hole constituting internal pressure reducing means, 47. 53 ... Also MGG.

Claims (5)

A rear seat side airbag device comprising an airbag that is deployed between a passenger seated in a rear seat with a reclining mechanism and a vehicle body side portion by gas generated from a gas generation source,
The backrest of the rear seat tilts to a position where a part of the back seat overlaps with a body side part other than the side door and a 100% overlap position where all overlaps with a body side part other than the side door. Configured to be deployable,
Detecting means for detecting that the backrest portion is disposed at the 100% overlap position when viewed from the side of the vehicle;
A side collision detection means for detecting a side collision of the vehicle;
An internal pressure reducing means for reducing the internal pressure in the deployed state of the airbag;
A control means for operating the internal pressure reducing means so as to reduce the internal pressure when a detection signal in which the backrest portion is disposed at the 100% overlap position is output from the detection means at the time of a side collision. A side airbag device for a rear seat characterized by comprising:   The rear airbag side airbag device according to claim 1, wherein the airbag is installed in the rear seat.   The side airbag device for a rear seat according to claim 1 or 2, wherein the airbag is provided with a vent hole, and the internal pressure reducing means reduces the internal pressure by increasing an opening degree of the vent hole.   The rear seat side airbag device according to claim 1 or 2, wherein the internal pressure reducing means is configured to reduce the internal pressure by suppressing an output of the gas generation source.   The said gas generation source is an inflator having a plurality of chambers, and the internal pressure lowering means is configured to reduce the internal pressure by selecting a chamber that generates gas from the plurality of chambers. Side airbag device for rear seats.

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